1. Field of the Invention:
The present invention relates to a connecting structure for a pressure detector with which the pressure detector is connected to an external instrument or a fluid passage in a pressurized fluid circuit.
2. Discussion of the Related Art:
FIG. 4 shows a conventional pressure detector 2. The pressure detector 2 has a body 4 shaped in a substantially rectangular parallelepiped and a display unit 6 provided on the upper surface of the body 4 for displaying a detected pressure. A screw 8 having a screw driver groove for setting a set pressure and an indicator lamp 10 for indicating an operational state of the pressure detector 2 are arranged around the display unit 6. An operator can set a desired set pressure by rotating the screw 8.
The body 4 contains a semiconductor pressure sensor (not shown), for example, for detecting the pressure of air introduced through a pressure-introducing port 12 and converting it into an electric signal. A lead wire 14 is drawn from the upper surface of the body 4, for energizing the pressure sensor and transmitting the detected signal to an external instrument (not shown).
A cylindrical member 16 having the pressure-introducing port 12 at its distal end is integrally coupled to the lower portion of the body 4. The cylindrical member 16 has a male thread 18 defined on its outer surface for connecting and fixing the pressure detector 2 to an external instrument or a fluid passage through which a pressurized fluid flows. When the pressure detector 2 is connected to the external instrument (not shown), the male thread 18 of the cylindrical member 16 is screwed into a hole of the external instrument on which a female thread is defined.
However, when the pressure detector 2 is connected to the external instrument, or when it is disconnected therefrom, the attachment or detachment must be performed by rotating the body 4 of the pressure detector 2 about the axis of the cylindrical member 16, thereby to screw the male thread 18 of the cylindrical member 16 into or out of the hole of the external instrument.
Thus, inconvenience arises in that when there is not enough space for the body 4 to be rotated in the place where the pressure detector 2 is to be connected to an external instrument or a fluid passage, it is hard or impossible to screw the male thread 18 of the cylindrical member 16 into the hole of the external instrument or the fluid passage. This inconvenience has greatly limited the possibility of the pressure detector 2 to be freely installed where it is necessary. Moreover, the above inconvenience has made piping work complicated, and a lot of time and labor must have been consumed therefor.